The newly branded Investec Champions Cup kicks off this weekend with all four Irish provinces in action.
There's a new format to contend with, with the 24 sides split across four pools, where they can't face teams from their own league and don't play the traditional home and away games.
When all the group fixtures are played we'll go into a round of 16 and then onto the quarters, semis and final, which takes place at Tottenham Hotspur Stadium on 25 May.
Here's how the opening round looks like for the Irish sides.
Connacht v Union Bordeaux-Bègles, The Sportsground, Friday 8pm
After a fast start in the BKT URC, Connacht have somewhat plateaued over the last two weeks. A heavy defeat away to the Bulls and heartbreaking loss to Leinster in Galway has served to halt the momentum that came with four wins from their opening five matches.
Pete Wilkins’ men sit in eighth in the table.
Bordeaux are in seventh place in the Top14, just outside the play-offs on points difference.
They have won five games and lost four. Their last outing was away to Oyonnax and they got their only away win of the season thanks to a fortuitous late try by France wing Louis Bielle-Biarrey.
Former France and Toulouse hooker Yannick Bru is the director of rugby at the club, while ex-Ireland Under-20 boss Noel MacNamara is the backs coach.
Les Bleus internationals Damian Penaud, Maxime Lucu, Matthieu Jalibert and Yoram Moefana are also among the stars Bordeaux can call upon for Friday’s clash.
Round 2-4 fixtures
Saracens (away) 16 December
Lyon (away) 13 January
Bristol Bears (home) 19 January
Munster v Aviron Bayonnais, Thomond Park, Saturday 5.30pm (live on RTÉ2, RTÉ Player and RTÉ Radio 1)
URC champions Munster are fourth in the table after four wins, a draw and two defeats to date.
Graham Rowntree’s side beat erstwhile league leaders Glasgow at the weekend, running in six tries in a 40-29 victory at Musgrave Park.
Bayonne, who were promoted from ProD2 in 2022, are in tenth place in the Top14, four points off the top-six.
They beat Montpellier 34-19 at the weekend.
Grégory Patat’s charges have won all four home games but have lost all five on the road.
Former France out-half Camille Lopez is the captain, while 63-cap Wallabies centre Reece Hodge is on the roster.
Round 2-4 fixtures
Exeter (away) 17 December
Toulon (away) 13 January
Northampton (home) 20 January
Bath v Ulster, The Rec, Saturday, 3.15pm
Ulster have been inconsistent so far this season and lost at home to Edinburgh last weekend, their third defeat of the season.
Dan McFarland's men have four wins under their belt and are seventh in the standings after seven rounds.
Bath, under former Munster head coach Johann van Graan, welcome Ulster off the back of a 41-24 win over Exeter last weekend.
They are second behind Sale on points difference in the Premiership, having won five and lost three of their eight matches.
Scotland out-half Finn Russell is the marquee name, while former Ireland lock Quinn Roux, ex-Munster flanker Chris Cloete and England forward Sam Underhill are also at the club.
Round 2-4 fixtures
Racing 92 (home) 16 December
Toulouse (home) 13 January
Harlequins (away) 20 January
Stade Rochelais v Leinster, Stade Marcel-Deflandre, Sunday 2.15pm (Irish time)
Leinster lead the way in the URC, their opening-round loss to Glasgow the only blotch on their record.
They needed a late try to beat Connacht last weekend, securing a bonus point in the 24-22 victory in Galway.
Ronan O’Gara’s La Rochelle have been Leinster’s nemesis over the last three seasons, winning the last two finals against Leo Cullen’s side, and a semi-final in 2021.
They come into this game off the back of a big home victory over Perpignan, 35-6. However, their form has been patchy and they’ve lost five and won four to date.
Gregory Alldritt, Pierre Bourgarit, Paul Boudehent, Antoine Hastoy and Jonathan Danty are just some of the star names at the club.
Round 2-4 fixtures
Sale Sharks (home) 16 December
Stade Francais (home) 13 January
Leicester Tigers (away) 20 January
FULL LIST OF CHAMPIONS CUP FIXTURES
Listen to the RTÉ Rugby podcast on Apple Podcasts, Spotify or wherever you get your podcasts.
Watch Munster v Bayonne in the Investec Champions Cup on Saturday from 4.45pm on RTÉ2 and RTÉ Player, or listen to commentary on RTÉ Radio 1.
Follow our live blogs and reports of every game for the Irish sides on www.rte.ie/sport and the RTÉ News app.
Donal Lenihan and Bernard Jackman preview the Champions Cup on Against the Head
